1. Technical Field
The present invention relates to roadway barrier systems. In particular, in relates to water filled barriers with upper, lower and central interlocking mechanisms to prevent vehicles from penetrating the barrier in the event of an accident.
2. Background Art
To control traffic in a variety of situations, such as construction, detours, or to separate lanes high-speed traffic, a variety of devices have been developed to prevent traffic from leaving the proper traffic line and entering an improper lane where an accident may occur. Once such set of devices comprises road barriers. The road barriers most often seen take one of two forms: solid concrete barriers or water filled barriers.
Concrete barriers were the among first to be developed. They provide a variety of features that are desirable in a barrier, such as substantial weight, simplicity of manufacture, and durability. While providing a practical solution for many applications, concrete barriers also have several drawbacks. For example, a concrete barrier is very heavy and requires special equipment to move and install it. In addition, since concrete barriers are often used on a temporary basis, the cost of moving these heavy objects is doubled due to the two trips required to install them and then to subsequently remove them. It would be desirable to have barrier which is light and easy to handle such that it would not require special equipment to be moved.
In addition to the problems caused by weight, concrete barriers typically do not have any interlocking mechanism to prevent them from separating upon impact by a vehicle. As a result, even though a barrier may be correctly placed, an out of control vehicle may climb over or push the barrier aside, penetrate another lane of traffic, and cause an accident. Attempts have been made to eliminate that problem. One attempt has been to form tabs in the ends of the barriers such that the weight of the adjacent barrier is used to help restrain the barrier from moving upon impact by a vehicle. However, barriers with tabs will typically disconnect from one another depending on the nature of the impact because the tabs are not positively secured.
To address problems related to the weight of the concrete barriers, an alternative lightweight barrier was developed. The lightweight barrier is typically fabricated from a synthetic material, such as plastic, polyethylene, polypropylene, or any other suitable material. These lightweight barriers are hollow structures that are easy to transport and manipulate. They do not need special equipment to be loaded onto or off of the transport vehicle. Further, they may be moved into position and adjusted by hand due to their light weight. Once the lightweight barriers are manually placed into position, they are filled with water resulting in a barrier which is equivalent in weight to a concrete barrier of similar size. At such time that the barrier is no longer needed, the water is drained from it. Once drained, the barrier is now light enough to be manually loaded onto a transport vehicle for removal. As a result, the inconvenience and expense resulting from the heavy weight of concrete barriers has been eliminated by the hollow water-filled barriers.
Unfortunately, existing water barriers have the same break through problem that concrete barriers have. In particular, when a vehicle strikes a water barrier it may push the barrier aside, enter another lane of traffic and cause an accident in the same manner that prior art concrete barriers did.
In the prior art barrier systems that use end tabs to connect adjacent barriers, the end tabs are typically positioned at the base of the barrier and provide limited resistance to movement of the barriers when impacted by a vehicle. In particular, if a vehicle strike's barrier at a higher location on the barrier wall, the barrier wall may separate and allow the vehicle to penetrate the barriers, enter an adjacent traffic lane and cause an accident. It would be desirable to have a barrier system in which adjacent barriers were secured at multiple points such that they would not separate if the barrier was struck by a vehicle at an unexpected height.
In attempting to deal with barrier separation problems, prior art systems have provided supplemental external devices that are used in conjunction with a barrier. One known system uses a form of metal exoskeleton that is secured to the outer surface of the barriers and extends across several barriers such that they are held together by the exoskeleton. Another known system uses cables that run across several barriers and are secured to several barriers in an attempt to prevent them from separating on impact. These systems add cost to the overall system and increase the amount of time required to install or remove the barriers. In addition, they generally secure only one area of the barrier. Because of this, if the barrier is struck in the right spot it may twist, resulting in separation from the adjacent barrier. It would be desirable to have a barrier structure that is resistant to separation and which does not require the installation of supplemental equipment such as complex exoskeleton or cable retention systems.
In addition to the safety problems caused by separation of barriers on impact, and the possibility of the exoskeleton, the cables, or the pins that hold the exoskeleton for the cables in-place, turning into projectiles upon impact by a vehicle, and the subsequent breakthrough of the vehicle into another lane traffic, prior art barrier systems typically have surfaces that are attractive to individuals for the purpose of printing graffiti because of the ease with which they may be written upon. As a result of the graffiti, many barriers become eyesores which result in additional expense due to the costs associated with having them cleaned. It would be desirable to have a barrier system which was resistant to graffiti.
When barriers are placed temporarily, for purposes such as construction, additional devices are usually used in conjunction with them. In particular, either warning lights or markers of some kind are used in conjunction with the barriers to provide warnings to motorists. It would be advantageous to have a barrier system that has an integral warning device to alert motorists of its presence.
While addressing some of the issues related to barrier systems, the prior part has failed to provide a barrier system which is lightweight, which is easy to manipulate by hand without special equipment, which is resistant to graffiti, and which has an integral warning system for motorists. More importantly, the prior art has failed to provide a barrier system that, when two barrier systems are joined together end-to-end, is resistant to separation upon impact by vehicle at any height due to multiple securing mechanisms at top, bottom and central locations.